Lipase in serum

Reference values ​​of the activity of lipase in serum are 0-190 IU / l.

Lipase is an enzyme that catalyzes the cleavage of glycerides into glycerol and higher fatty acids. This enzyme in the human body is produced by a number of organs and tissues, which makes it possible to distinguish between lipase of gastric origin, pancreas, lung lipase, intestine, leukocytes, etc. The most important from a clinical point of view is pancreatic lipase. Pancreatic lipase plays a major role in the digestion of fats. Since the main source of lipase is the pancreas, with its diseases there is a significant release of the enzyme into the circulating blood. Determination of lipase activity in the blood is considered the most informative criterion for the diagnosis of acute pancreatitis. There is a misconception that in acute pancreatitis, the lipase content in the blood increases later than the amylase, but it remains elevated for a longer time. In fact, lipase activity increases and decreases in parallel with an increase and decrease in amylase activity, but the normalization of its level occurs later than amylase. Sometimes the activity of lipase in the blood rises earlier than amylase, and remains elevated for a long time.

In acute pancreatitis, lipase activity in the blood increases within a few hours after the onset of the disease, reaching a maximum( up to 200 times) after 12-24 hours, and remains elevated for 10-12 days. The prognosis of the disease is considered unfavorable if the lipase activity in the blood rises by 10 times or more and does not decrease to a 3-fold excess of the norm within the next few days. The diagnostic sensitivity of lipase in the serum in acute pancreatitis is 86%, specificity is 99%( Wallach, J. M.D. et al., 1996).Simultaneous determination of the activity of a-amylase( in blood and urine) and lipase is the basis for the diagnosis of acute pancreatitis. An increase in both or one of the enzymes reveals in 98% of patients with acute pancreatitis.

Unlike amylase, lipase activity does not increase with parotitis, ectopic pregnancy, lung cancer, appendicitis. The edematous form of acute pancreatitis, as a rule, is not accompanied by an increase in lipase activity;fatty pancreonecrosis is characterized by a marked increase in its activity, persisting up to 2 weeks;and with hemorrhagic pancreatic necrosis it increases( on average 3.5 times) for a short time on the 3-5th day of the disease. When purulent pancreatitis increases the activity of

, lipase in the blood is usually not detected. Sometimes an increase in lipase activity is found in patients with pancreatic cancer, chronic pancreatitis, with a cyst in the pancreas.

Serum lipase activity is highly sensitive, especially with regard to the diagnosis of acute alcoholic pancreatitis, while for patients with obstruction of the bile duct, large duodenal papilla and pancreatic ducts, high amylase activity is characteristic. In this regard, to establish the etiology of acute pancreatitis, the lipase-amylase coefficient is sometimes calculated: the ratio of lipase activity to serum amylase activity. The value of the lipase-amylase coefficient above 2 allows to diagnose acute alcoholic pancreatitis( sensitivity - 91%, specificity - 76%).Only in patients with acute alcoholic pancreatitis, the coefficient may be higher than 5.

Increased lipase activity in the blood may occur with intestinal infarction, peritonitis, biliary colic. An increase in the activity of lipase in the blood during the destruction of adipose tissue - fractures of bones, wounds of soft tissues, after operations, in breast cancer.

Hyperlipazemia with uremia and arthritis is a consequence of stagnation in the pancreas.